Add device and output selection support

[bsneed]

• Adds AudioDevice class.
• Adds localDevices property to retrieve a list of visible audio output devices.
• Adds outputDevice property to get / set the audio output device.
• Fixed deadlock in AVPlayerWrapper where the delegate can issue a state change while still inside the lock.
• Depends on #80

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 74.70588% with 43 lines in your changes are missing coverage. Please review.

Project coverage is 77.54%. Comparing base (4d3c1db) to head (8dd0a04).

Files	Patch %	Lines
Sources/SwiftAudioEx/Utils/Devices.swift	69.72%	33 Missing :warning:
Sources/SwiftAudioEx/AudioTap.swift	85.71%	7 Missing :warning:
Sources/SwiftAudioEx/AudioItem.swift	0.00%	2 Missing :warning:
Sources/SwiftAudioEx/AudioPlayer.swift	50.00%	1 Missing :warning:

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #85      +/-   ##
==========================================
- Coverage   78.33%   77.54%   -0.80%     
==========================================
  Files          17       19       +2     
  Lines        1288     1456     +168     
==========================================
+ Hits         1009     1129     +120     
- Misses        279      327      +48     

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